Cleaning. - TM-5-5430-226-120062

TM 5-5430-226-12

4-19. 4-INCH GATE VALVE MAINTENANCE - cont.

(6) Remove packing nut (3), gland spring (4), packing ring (5) and packing gland (6).

(7) Remove eight nuts (32), lockwashers (33), and bolts (7).

(8) Remove bonnet (8), gasket (9) and attached parts from valve body (15).

NOTE

If needed, tap bonnet (8) with mallet to loosen sealing surfaces.

(9) Remove two screws (13) and separate discs (12 and 14) from disc riser (11).

(10) Remove disc riser (11) from stem (10).

(11) Unscrew stem (10) from bonnet (8) and remove stem.

c. Cleaning.

(1) Wash all components with clean water and detergent.

(2) Rinse components in clean water and dry with wiping rag.

d. Inspection.

(1) Inspect bonnet (8), valve body (15) and flanged couplings (17 and 30) for cracks, scored

mating surfaces, stripped threads and corrosion.

(2) Inspect for bent stem (10). Inspect for galled or stripped threads.

(3) Inspect sealing surfaces of discs (12 and 14) for deep scratches and cracks.

e. Repair. Replace damaged components. Do not re-use sealing components. Replace all O-rings and gaskets.

f. Assembly.

(1)

Screw stem (10) into bonnet (8).

(2)

Install disc riser (11) on stem (10).

(3)

Install discs (12 and 14) on riser (11) with two screws (13).

(4)

Turn stem (10) counterclockwise until discs (12 and 14) retract into bonnet (8).

(5)

Position gasket (9) on valve body (15). Guide bonnet (8) and attached parts onto valve body.

(6)

Install eight bolts (7), lockwashers (33) and nuts (32).

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